THE MORE THINGS CHANGE Ariadne is now C. Tsar’s, but you can still get the same grilled squid with hummus you used to know.

It can be very good when a fine chef moves downmarket, adding focus and financial discipline to pure talent. Christos Tsardounis has done it twice in recent years, moving from his initial bistro, Aspasia in Cambridge, to the more modest (but larger) second restaurant, Ariadne in Newtonville (and then closing Aspasia), and now paring down Ariadne into C. Tsar's. His deal has always been a Mediterranean framework on local produce, and his relaxation of the style from Aspasia to Ariadne made the latter one of the most comfortably wonderful dining spots around Boston. The new menu is even more back-to-basics with the addition of superb thin-crust pizza, but despite falling prices, I'm less in love with the same room and some of the same dishes.

Crusty bread and sweet butter are still the openers. Another holdover is grilled squid with hummus ($10), which combines lean seafood, flash-seared to keep it tender, with the richness of the bean paste, and some arugula for contrast. The old confit duck leg ($11) is waiting for us, as well, with a simplified but effective garnish of a highly spiced poached pear.

New to my notice is the Mediterranean plate ($12), with a good (not great) chunk of feta, cured olives, hummus, a novel tabbouleh with cucumber, grilled peppers and onions, tzatziki with restrained garlic, and lovely grilled flatbreads. A Greek salad ($8) outdoes the usual with extra cheese, grape tomatoes with actual flavor, and the croutons more common in Caesar salad.

The most striking change is the introduction of thin-crust pizza, but why not? Even as an appetizer, the pizza margherita ($10), eight slices of terrific crust with some char on the bottom, is a pure evocation of Italia. Now admittedly, the original margherita was an Italian flag showing equal parts tomato sauce, basil, and cheese. But the present tilt toward cheese with grape tomatoes and leaves of basil may be a superior proportion. It is awfully good pizza, and there are 10 other kinds, plus options to permute.

Tagliatelle Bolognese ($15) is a best buy, as good as some downtown at 30- to 50-percent higher prices. The secret is the chef's own chicken sausage, minced up with beef, tomato, basil, and a bit of cream, on wide noodles of homemade pasta. The moussaka ($16) has the same thrill of familiarity done one better, this time in ground meat scented with cinnamon, layered with bechamel and eggplant.

Paella ($18) has been the ruin of many a chef in Boston. This one gets the right kind of short-grain rice, keeps it a little underdone as though making risotto (not standard practice, but good), doesn't overcook the seafood (fish, mussels, and clams in the shell), possibly shorts the saffron, and doesn't use chicken. Tsardounis also likes it a little soupy, like jambalaya. I could join him on that.

For more of the luxury of Ariadne, have the sea scallops ($25): six seared and arranged on a kind of chowder not unlike Brazilian pizza (if you haven't had Brazilian pizza yet, watch for it) with bacon, corn, asparagus, and roast carrots on mashed potatoes. Artful dribbles of basil oil remind us that it is still the same chef back there.

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